1. Field of the Invention
The present invention relates to setting color recognition parameters for recognizing specific colors from an image.
2. Description of the Related Art
There is a need for recognizing specific colors from an image for recognizing color markers from the image. A color is recognized on a computer by determining a specific color by determining whether a value indicating a color of each pixel on a screen exists within a predetermined range.
For example, to detect a red color, pixel color-difference signals Cb, Cr forming a pixel have been specified in the following range: −1<Cb<+3 and +25<Cr<+127
In this case, to specify the red color, a set of values (−1, +3, +25, +127) has been used.
Generally, if the lighting or other conditions change, the range for specifying a specific color need be readjusted for the conditions. For example, color recognition parameters having been used under a fluorescent lamp need be readjusted under an incandescent lamp.
Conventionally, an operator has adjusted the color recognition parameters by adjusting values manually while observing a recognition rate.
This kind of color recognition parameter adjustment, however, requires an operator to have a lot of skill and to repeat the same work for each color inefficiently.
In addition, this kind of color specification method using a set of numerical values is not intuitive, which leads to a difficulty in specifying a recognized color.